Description of problem: The warning will not correct when adding virtual network. Version-Release number of selected component (if applicable): virt-manager-0.6.1-6.el5 How reproducible: 100% Steps to Reproduce: 1. Launch virt-manager 2. Open "Host Details" window by "Edit --> Host Details", go to page of "Virtual Networks" 3. Add a new network follow the wizard, specify "192.168.0.0/24" on page of "Choosing an IPv4 address space". 4. Change "192.168.0.0/24" to "192.168.0.0/23", then change to "192.168.0.0/22"......"192.168.0.0/13" 5, Change to "192.168.0.0/12" 6, Cancel the "Create new virtual network" window and add a new one, specify the "192.168.0.0/15" on page of "Choosing an IPv4 address space". Actual results: There is none warning at step 3 and step 4. There will be warning at step 5. There will be warning at step 6. Expected results: But the largest CIDR block (subnet mask) is 192.168.0.0/16 (255.255.0.0) Additional info: This condition also happens on 10.0.0.0/8 private network, the user can specify 10.0.0.0/7
The reporters analysis wasn't correct: 192.168.0.0/13 is a valid CIDR block. 168 as a bit mask looks like: 10101000 This means the bottom 3 bits aren't required to specify the network address (if assumed to be all 0). This means only 12 total bits are required to specify the network address (8 for 192, 4 for 168). That means any host mask from /32 to /13 is valid, but anything less is an error. Closing as NOTABUG.